Avaliação da autorregulação cerebral em jovens saudáveis filhos de normotensos e filhos de hipertensos essenciais: uma análise simbólica e de transferência de função

Abstract

BACKGROUND: Although Systemic Arterial Hypertension (SAH) is a clinical entity recognized for decades and extensively studied, its cause is unknown in about 95% of cases. There is evidence that the impairment of cardiac autonomic modulation would be related to the onset of the disease. The analysis of the Heart Rate Variability and the analysis of the cerebral autoregulation through the function transfer analysis have been shown to be promising methods in the evaluation of the autonomic cardiac control and the cerebral vasomotor regulation, respectively. OBJECTIVES: To evaluate the autonomic response at heart level and cerebral vascular level in children of hypertensive parents in comparison to children of normotensive parents. METHODS: Cross-sectional, descriptive study conducted at University Hospital / UFS from March 2017 to August 2018, including healthy students between 18 and 30 years. The experimental group consisted of children of parents (father and / or mother) hypertensive and the control group by children of normotensive parents. Those who fulfilled the inclusion criteria were submitted to a sympathetic stimulation test at the TILT table and had their arterial pressures and flow velocity in the Average Cerebral Artery monitored at rest and after elevation. The data were studied for analysis of heart rate variability and function transfer analysis. RESULTS: Regarding the symbolic analysis, there was no statistically significant difference in the 0V, 1V, 2LV and 2LV patterns between the groups, either at rest or after the stimulus. In relation to the function transfer analysis, the experimental group showed a significant increase in the coherence and gain in the control group and a discrete increase in the children of hypertensive parents, showing a statistically significant difference (p <0.05). The Phase analyze did not show statistical relevance between groups CONCLUSION: It was not possible to identify, in this sample, statistically relevant differences in the autonomic cardiac modulation between the groups. However, there seems to be an incipient loss of coherence and gain between BP and cerebral blood flow in children of hypertensive patients, especially after de sympathetic stimulation.